High pressure apparatus



Aug. 24, 1965 P. KE FRYKLUND HIGH PRESSURE APPARATUS Filed Dec. 18, 19623 Sheets-Sheet 1 Aug. 24, 1965 P. AKE: FRYKLUND HIGH PRESSURE APPARATUS3 Sheets-Sheet 2 Filed DeC. 18, 1962 Allg- 24 1965 P. AKE FRYKLUND3,201,828

HIGH PRESSURE APPARATUS Filed Dec. 18, 1962 3 Sheets-Sheet 3 UnitedStates Patent O 3,201,828 HIGH PRESSURE APPARATUS Per lre Frylrlund,Robertsfors, Su/eden, assigner to Allmanna Svenska ElektrishaAhtiebolaget, Vasteras, Sweden, a Swedish corporation Filed Der. 18,1%2, Ser. No. 245,477 Claims priority, application Sweden, Dec. 27,1961, 12,962/61, 12,963/6l 12 Claims. (Cl. l8-l6.5)

With apparatus for generating very high pressures, for example apparatuswhich is used for conversion of graphite to diamond when the pressuresare several tens of thousands of atmospheres, it is desirable that thepressure is generated in as large a volume as pos-sible and that themovement of `the punches movable for the pressure generation is .assmall as possible. A large volume gives large yield of reactionproducts, and small movement in the punches decreases Vto a great extentfriction losses and facilitates the possibilities of making good sealsfor the pressure.

According to the present invention high and uniform pressures can beproduced in large volumes with small movements in the members whichgenerate .or transfer t-he pressure to the pressure chamber.

The invention relates to a high pressure apparatus comprising 4apressure chamber which includes two end surfaces and side surfaces, andwhich has an axis running through the end surfaces, in which a pressureis generated with a pressure-transmitting mechanical means, movabletowards the interior of the pressure chamber. The high pressureapparatus according to the invention is characterized in that thepressure-transmitting means consists of several blocks, separated Ibyintervening gaps, which have surfaces turned towards the pressurechamber and forming together the pressure chamber side surfaces and thatsubstantially centrally in the pressure cham-ber an inner body withsmall compressibility is arranged protected from the inluence of .amaterial or mixture to be subjected to pressure in the pressure chamber,e.g. comprising a carbonaceous substance to be converted to diamond, andwhich between itself and the surfaces of the blocks turned towards thepressurechamber forms a tube-shaped space for the material to besubjected to pressure, and that the end surfaces of the pressure chambercomprise pressure-resisting means sealed to the blocks, lwhich duringthe movement of the `blocks towards the interior of the pressure chamberhave a position ixed in axial direction in relation to the pressurechamber.

The seal between the pressure-transmitting means and thepressure-resisting means at the end surfaces may be effected withdeformable sealing means.

The inner body may suitably have a cylindrical or conical outer surfaceand an axis coinciding with that of the pressure chamber.

According to a suitable embodiment the innerbody may consist of ya pegwith an axis substantially coinciding with that of the pressure chamber,which peg is -axially movable and tapered, an-d of a case arrangedaround the peg and slotted in separate parts, the inner surfaces ofwhich tit the external surfaces of the peg and the separate parts ofwhich lare displaceable towards the side surfaces of the pressurechamber by displacing the peg in its axial direction. :If the inner bodyis shaped in this way the special advantage is attained that thematerial to ice be subjected to pressure can be precompressed before itis subjected to compression through the blocks.

The inner body with small compressibility can be protected against theinliuence of the material or material mixture by being formed of amaterial which in itself is resistant to the material or mixture underthe conditions prevailing at the border surface between the material ormixture and the body. The interior body may also be protected againstthe influence of the material or mixture by being surrounded with aprotective case which prevents the material or mixture from coming intodirect contact with it.

The blocks of the pressure-transmitting -means may be so shaped that onthe outside they form together a conical surface and be arranged in asurrounding mechanically strong pressure-absorbing casing with aconi-cal inner wall which llits the common outer surface of the blocks,so that through .axial displacement of the pressure-transmitting meansin relation to the pressure-absorbing casing .the pressure-transmitting,blocks may be displaced t-owards the interior of the pressure chamber.

The invention will be more closely explained by describing .a number ofembodiments referred to on the accompanying drawing. FGURE l shows alongitudinal section through a high pressure -apparatus with acylindrical pressure chamber, in the middle of which an inner body withsmall compressibility is arranged, which consists of .two parts, yaninner peg and a slotted case surrounding this.

FIGURE 2 shows a cross-section of the apparatus shown in FIGURE l.

FIGURES 3, 4 and 5 show details of the high pressure apparatus shown in-FGURE l on a larger scale, FlG- URES 3 `and 4 particularly the pressurechamber in longitudinal section and cross section respectively.

FIGURE 6 shows a detail of a high pressure apparatus Wit-h .acylindrical inner body formed as .a single part arranged therein.

In the high pressure apparatus shown in FlGURES 1 and 2 the pressurechamber, which is cylindrical, is limited along the envelope surface ofthe sector-shaped blocks ltltl, the parts lill of which situated nearestthe pressure chamber are suitably made of harder material than the partssituated further away. The sector-shaped blocks 100, between which thegaps 102 are situated, form together a pressure-transmitting means inwhich the border surfaces M3, ldd and MD5 are conical and the bordersurface 10d is cylindrical. The gaps M2 are in planes running throughthe symmetry axis of the pressure chamber and their width is, in apreferred embodiment, sufilcient so that Contact between the walls ofadjacent blocks facing each other does not occur even when they haveaproached each other so much that the intended pressure has been reachedin the pressure chamber. At the end surfaces, the pressure chamber islimited by the internally circular surfaces of the conical pistons 107and M28 (in a higher position when pressure is applied) the parts 25.69and 110 of which situated nearest the pressure chamber suitably are madeof harder material than the parts situated further away. Thepressure-transmitting means consisting of the sector-shaped blocks ltllis externally surrounded by a mechanically strong metal casing lllserving as pressure-absorbing means, said casing having internallyconical form adapted to the exterior of the pressure-transmitting means.Between the said pressuretransmitting means and the casing 111, a layer149 of a lubricating means is arranged, e.g. graphite, molybdenumdisulphide, oil, etc. Above the casing a strong metal cylinder 112 isarranged, which is insulated from the casing by a layer 113 of asbestos,mica, paper, pressboard or similar material. Between the parts 100 (101)and 107 (109) a layer 114 of such insulating material is also inserted.Between the piston 107 and the cylindrical top plate 115 a compressionchamber 116 is arranged, filled with a compression medium such as, forexample, oil, water or other suitable medium. The pressure in thecompression chamber may be regulated with an adjustable valve 117arranged in a conduit 161 between the chamber 116 and a container notshown. Above the plate 115 and the metal cylinder 112 a stationarysupport 153 is arranged. The plate 115 is arranged with the peg 11Swhich corresponds to the recess 119 in the piston 107 so that it may beaxially displaced. The chamber 116 is sealed at the recess by the seal155, suitably of rubber. The compression chamber is sealed to thecylinder 112 by the sealing rings 120, suitably of rubber. Instead ofthe compression chamber 116 a mechanical spring means with adjustablespring pressure may be used.

In the lower piston 103 a conical peg 121 of a material with smallcompressibility is fastened. As more clearly shown by FIGURES 3 and 4the conical body 121 has on the uppermost end surface a layer 122 ofinsulating material, for example asbestos, talcum, etc., for insulationagainst the upper piston, and is nearest the envelope surface surroundedby an internally conical and externally cylindrical slotted case,consisting of sector-shaped separate parts 123. The peg 121 and theparts 123 form together the previously mentioned inner body with smallcompressibility. This part is surrounded by tube-shaped insulation 124consisting of, for example, pyrophyllite or talcum. Outside thisinsulation the reaction mixture 125 is arranged, for example consistingof a mixture of graphite and a metal such as nickel or iron. Bysubjecting this mixture to very high pressure, several tens of thousandsof atmospheres, and high temperature, over 1000 C., the graphite can beconverted to diamond. The reaction mixture is surrounded by anexternally tube-shaped insulation 126 suitably of the same material asthe insulation 124. The spaces between the blocks 123 are sealed againstthe material outside by the axially running sealing strips 127 havingparallel-trapezium shaped cross-section, and which lie against axiallyrunning bevelledv surfaces 128 and 129 of neighbouring blocks. In asimilar way the gaps 102 between the blocks 100 (101) are sealed to thepressure chamber with the axially running sealing strips 130, likewisewith parallel-trapezium shaped crosssection. Each sealing strip 130 liesagainst axially running bevelled surfaces 131 and 132 of neighbouringblocks. The pistons 107 and 108 are nearest to the pressure chamberprovided with circular discs 139 and 140 of steel or cemented carbidewhich towards the pressure chamber are bevelled as is seen more clearlyfrom FIG- URE 5. Against the bevelled surface 141 of the discs 139 liesa sealing ring 142 with a surface 143 and with another surface 144 abovethe uppermost part of the insulation 126 against the blocks 100 (101).The ring 142 is plastically deformable. The metal discs 139 and 140 neednot form separate arrangements but may be parts of the arrangements 107and 10S. Between the parts 139 and 123 an insulating layer 159, forexample of asbestos, talcum or similar material, is arranged. Againstthe lower disc 140 another ring 160 of plastically deformable materialis correspondingly situated. As seen from FGURE 3 this ring may liedirectly against the blocks 100 (101) without intermediate insulation.Through the pistons 107 and 108, the body 121 and the pegs 118 a coolingchannel consisting of parts 133, 134, 135 and 136 is arranged, throughwhich a cooling medium, for example water, spirit, oil or the like maybe conducted. Mainly at the end surfaces of the pressure chamber rings137 and 13S of conducting material, for example steel, copper or thelike are arranged for supplying electrical current to the reactionmixture. If this consists of graphite mixed with metal it has sufilcientconductivity to be directly subjected to resistance heat treatment. Ifthe reactor mixture has not such good conductivity, the heating may becarried out by means of tubes, discs, threads, spirals or other bodiesof electrical resistance material embedded in the reaction mixture. Thecurrent may be supplied via conduit 145 on the piston 103 and the piston108, and led away via the piston 107 and the cable 146 arranged in achannel 147 in the casing 111.

The reaction mixture may be subjected to pressure by displacing thepiston 103 upwards with a partly shown hydraulic press 154 ofconventional type. A certain precompression of the contents of thepressure chamber then occurs merely because the body 121 is whollycarried into it. The consequence is namely that the slotted partconsisting of the blocks 123 is displaced towards the envelope surfaceof the pressure chamber. When the ring 156 which is arranged around thelower part of the piston 108 or is a part of the piston 10S meets theplane surface 157 of the blocks 100, these begin to be displaced upwardsin the stationary casing 111 along the common sliding surface. Sincethere is always a gap between the surfaces and 148 and gaps betweentheblocks 100 (101) this causes a displacement of the blocks 100 (101)towards the middle of the pressure chamber, so that the reaction mixtureis compressed between the body 121 and the blocks 100 (101). The sealingrings 142 and 160 at the rings 139 and 140 are thus deformed. If therings 142 and 160 are arranged in direct contact with the reactionmixture the rings 137 and 138 are unnecessary. The supporting pressureon the upper end surfaces of the pressure chamber may be maintained atthe required level by adjustment of the pressure in the compressionchamber 116. At the same time the position for the surface of the upperpiston facing towards the pressure chamber may be displaced in axialdirection and corrected according to the movements of the separateblocks. The supporting pressure on the lower end surface of the pressurechamber is exercised by the upper circular surface of the piston 103.

In FIGURE 6 another embodiment of the invention is shown, in which thepressure chamber is arranged differently from that shown in FIGURE 1,but the other details are the same. On the pistons 107 (109) and 108(110) circular metal discs 150 and 151 are arranged nearest the pressurechamber. On the disc 151 a cylindrical inner body 152 with smallcompressibility and consisting of one part is arranged, and immediatelyaround this a material to be subjected to pressure, for examplemolybdenum disulphide. The body 152 may here be composed of for examplestainless steel which is not inuenced by the material. Duringapplication of pressure on the movable "sector-shaped blocks thematerial is compressed according to the envelope surface of the body152.

The lower piston 108, in the same way as the upper piston 107, may alsobe arranged to exercise an adjustable support pressure on the endsurfaces of the pressure chamber. Outside the piston 108 (without thering 156) a compression chamber with adjustable pressure may be arrangedin an analogous way as outside the piston 107, which compression chamberis radially limited by a mechanically strong tube, the ends of which lieagainst the surface 157 and the piston 154, and axially limited by thelower surface of the piston 108 and a plate lying along the uppersurface of the piston 154, corresponding to plate of the upper piston107.

The inner body with small compressibility including parts 121, 123 and152 may, inter alia, be manufactured from a metal such as iron, nickel,cobalt, chromium, manganese, molybdenum, aluminium, tungsten, tantalum,zirconium, titanium, copper, and alloys of these such as, for

r example, a tool steel with a hardness of RC 65 (e.g. C 550,V

Fagersta Bruks AB, Sweden), a high speed steel with a hardness of RC 68(eg. WKE 4, Fagersta Bruks AB, Sweden), a stainless steel with ahardness of RC 50 (e.g. RRNJ 44, Fagersta Bruks AB, Sweden), varioustypes of brass and bronze, Monel (31% Cu, 67% Ni, 2% Fe, Mn, Si), ferroniobium (S0-60% Nb, 40-50% Fe), Nichrome (80-90% Ni, 10-20% Cr) andcertain aluminium alloys. Further, sintered alloys, inter alia, of thecemented carbide type (c g. Coromant H05, H10, Sandvikens Jernverks AB,Sweden, Uddia H20, Uddeholms Jrnverks AB, Sweden, containing tungstencarbide and 4-10% cobalt). The material in the inner body is chosen ineach particular case, inter alia, according to the conditions which thematerial to be treated in the pressure chamber is to be subjected to.

As examples of materials surrounding the pressure chambers in the shownhigh pressure apparatus may be mentioned: for the parts 100, 101, 107,108, 109, 110, 139, 140, 150, and 151 a cemented carbide (e.g. Carboloy999, General Electric Co., U.S.A., or Coromant H05, Sandvikens JernverksAB, Sweden) or a high speed steel with a hardness of RC 65-67 (e.g. WKE4, Fagersta Bruks AB, Sweden), for the part 111 a toughened steel with ahardness of RC 45 (e.g. RO 7155, Bofors AB, Sweden), for the parts 127and 130 a tempered steel with a hardness of RC 65 (e.g. ROB 21, BoforsAB, Sweden), and for the parts 142 and 160 for example a toughened steelwith a hardness of RC 50 (e.g. RO705, Bofors AB, Sweden), an austeniticstainless steel (e.g. Avesta 832, Avesta, Sweden), copper-berylliumalloys of various compositions (e.g. containing about 97.5% Cu, 2% Beand 0.25% CO), chromium-nickel-iron alloys of various compositions (e.g.containing 7% Fe, 78% Ni and 15% CO).

I claim:

1. High pressure apparatus comprising an outer pressure absorbing means,a pressure chamber including means forming two end surfaces and meansforming side surfaces and having an axis running through the endsurfaces, the means forming said side surfaces of the pressure chambercomprising a plurality of blocks arranged around the pressure chamberand having side surfaces facing each other, there being gaps betweensaid side surfaces of the blocks, said blocks being movable in the axialdirection in said outer pressure absorbing means, said blocks and saidouter pressure absorbing means having cooperating means to producemovement of the blocks towards the interior of the pressure chamber inresponse to axial movement of the blocks in one direction forcompressing a material arranged in the pressure chamber, said meansforming end surfaces of the pressure chamber being pressure-resistingmeans sealed to the blocks and both mounted for axial movement in thesame direction with respect to the outer pressure absorbing means tofollow the axial movement of the blocks.

2. High pressure apparatus as claimed in claim 1, having deformablesealing means sealing said pressure chamber to said gaps between saidblocks.

3. High pressure apparatus as claimed in claim 2, in which saiddeformable sealing means is slidably arranged between said pressureresisting means and said blocks.

4. High pressure apparatus comprising an outer pressure absorbing means,a pressure chamber including means for-ming one rst and one second endsurface and means forming side surfaces and having an axis runningthrough the end surfaces, said means forming side surfaces of thepressure chamber comprising a plurality of blocks arranged around thepressure chamber and having side surfaces facing each other, there beinggaps between said side surfaces of the blocks, said blocks beingarranged in an outer pressure absorbing means, said outer pressureabsorbing means comprising a member having therein a hole with an axiscommon to that of the pressure chamber and with a constantly decreasingcross-section in one direction of the axis, said blocks having externalsurfaces fitting the surfaces of the hole of the pressure absorbingmeans and being displaceable in the direction of such axis with respectto the pressure absorbing means for effecting a movement of the blockstowards the interior of the pressure chamber for pressure generation inthe pressure chamber, said means forming the first end surface of thepressure chamber being constituted of a rst axially movablepressure-resisting means, said means forming the second end surfacebeing constituted of a second axially movable pressure-resisting means,and axially acting pressure means for producing movement of said blocksin the direction of decreasing cross-section of the hole, said iirst andsaid second pressure-resisting means being sealed to the blocks and bothmounted for axial movement in the same direction with respect to theouter pressure absorbing means to follow the axial movement of theblocks.

5. High pressure apparatus as claimed in claim 4, in which a lubricationlayer is arranged between the surfaces of the hole of the pressureabsorbing means and the surfaces of the blocks adjacent thereto.

6. High pressure apparatus as claimed in claim 4, in which said axiallyacting pressure means causing the displacement of the blocks is arrangedoutside said rst end surface of the pressure chamber and constitutes apressure support for said rst pressure-resisting means.

7. High pressure apparatus as claimed in claim 4, in which said pressurechamber has a cylindrical form, said hole of the pressure absorbingmeans having a conical form, said blocks forming together a body with anexternally conical form litting the hole of the pressure absorbingmeans, said blocks being sector-shaped and said first and said secondpressure-resisting means having a conical form and having circularsurfaces turned towards the pressure chamber.

8. High pressure apparatus comprising an outer pressure absorbing means,a pressure chamber including means forming one first and one second endsurface and means forming side surfaces and having an axis runningthrough the end surfaces, said means forming the side surfaces of thepressure chamber comprising a plurality of blocks arranged around thepressure chamber and having side surfaces facing each other, there beinggaps between said side surfaces of the blocks, said outerpressure-absorbing means comprising a member having therein a hole withan axis common to that of the pressure chamber and with a successivelydecreasing crosssection in one direction of the axis, said blocks havingexternal surfaces fitting the surfaces of the hole of thepressure-absorbing means and being displaceable in relation to thepressure-absorbing means in the duration of such axis for effecting amovement of the blocks towards the interior of the pressure chamber forpressure generation in the pressure chamber, said means forming thefirst end surfaces of the pressure chamber comprising a first axiallymovable pressure-resisting means including first means to exert anadjustable pressure at the rst end surface to equal the pressure blockstowards the interior of the pressure chamber, said means forming thesecond end surface of the pressure chamber comprising a second axiallymovable pressure-resisting means including second means to exert anadjustable pressure towards the pressure chamber for adjusting thepressure at the second end surface to equal the pressure generated inthe pressure chamber upon the displacement of the blocks towards theinterior of the pressure chamber, said rst and said secondpressure-resisting means being sealed to the blocks and both mounted foraxial movement in the same direction with respect to the outer pressureabsorbing means to follow the axial movement of the blocks, and axiallyacting pressure means for producing movement of said blocks in thedirection of decreasing cross-section of said hole, said pressure meanssupporting said first pressureresisting means.

9. High pressure apparatus as claimed in claim 8, in which said iirstpressure-resisting means and said blocks have opposed surfaces thereontransverse to such axis.

10. In high pressure apparatus as claimed in claim 1, an inner body ofsmall compressibility substantially centrally positioned in the pressurechamber, said inner body forming between itself and the surfaces of theblocks turned towards the pressure chamber a tube shaped space for thereaction mixture to be subjected to pressure.

11. High pressure apparatus as claimed in claim 10 in which the innerbody is surrounded by a casing preventing the material being compressedfrom coming into direct contact with the inner body.

12. High pressure apparatus as claimed in claim 1), said inner bodycomprising a peg with an axis substantially coinciding with that of thepressure chamber and being movable in the direction of the axis andtapered,

References Cited by the Examiner UNITED STATES PATENTS 2,737,998 3/56Meanor et al. 2,947,034 8/ 60 Wentorf. 3,096,544 7/63 Lundblad.3,105,994 l0/ 63 Gerard et a1. 3,123,862 3/ 64 Levey.

and a case around the peg comprising several separate 15 WILLIAM J.STEPHENSON, Primary Examiner.

1. HIGH PRESSURE APPARATUS COMPRISING AN OUTER PRESSURE ABSORBING MEANS, A PRESSURE CHAMBER INCLUDING MEANS FORMING TWO END SURFACES AND MEANS FORMING SIDE SURFACES AND HAVING AN AXIS RUNNING THROUGH THE END SURFACES, THE MEANS FORMING SAID SIDE SURFACES OF THE PRESSURE CHAMBER COMPRISING A PLURALITY OF BLOCKS ARRANGED AROUND THE PRESSURE CHAMBER AND HAVING SIDE SURFACES FACING EACH OTHER, THERE BEING GAPS BETWEEN SAID SIDE SURFACES OF THE BLOCKS, SAID BLOCKS BEING MOVABLE IN THE AXIAL DIRECTION IN SAID OUTER PRESSURE ABSORBING MEANS, SAID BLOCKS AND SAID OUTER PRESSURE ABSORBING MEANS HAVING COOPERATING MEANS TO PRODUCE MOVEMENT OF THE BLOCKS TOWARDS THE INTERIOR OF THE PRESSURE CHAMBER IN RESPONSE TO AXIAL MOVEMENT OF THE BLOCKS IN ONE DIRECTION FOR COMPRESSING A MATERIAL ARRANGED IN THE PRESSURE CHAMBER, SAID MEANS FORMING END SURFACES OF THE PRESSURE CHAMBER BEING PRESSURE-RESISTING MEANS SEALED TO THE BLOCKS AND BOTHE MOUNTED FOR AXIAL MOVEMENT IN THE SAME DIRECTION WITH RESPECT TO THE OUTER PRESSURE ABSORBING MEANS TO FOLLOW THE AXIAL MOVEMENT OF THE BLOCKS. 